Under "Using The Access Token" If the user changes their password, the access token expires or the user deauthorizes your app in the App Dashboard, the

Under "Using The Access Token" If the user changes their password, the access token expires or the user deauthorizes your app in the App Dashboard, the Graph API will issue an HTTP 400 and return the error in the body of the response: from http://developers.facebook.com/docs/authentication/ http://developers.facebook.com/docs/authentication/